Dipper tooth



c. B. ANDREWS Feb. 2 1926.

DIPPER TOOTH Filed Feb. 14, 1925 Patented Feb. 2, 1926.

UNITED STATES PATENT OFFICE.

CHARLES B. ANDREWS, OF HIGH BRIDGE, NEW JERSEY, ASSIGNOR T0 TAYLOR-WEAR- I'ON IRON AND STEEL COMPANY, OF HIGH BRIDGE, NEW JERSEY, A CORPORA- TION OF NEW JERSEY.

mrrnn room.

I Application filed February 14', 1925. Serial Zli'o. 9,230.

ments in two part reversible digging teeth,

commonly known as dipper teeth.

For a number of years it has been the practice to construct the point and base of manganese steel because of the remarkable wear resistance that metal exhibits when its inherent characteristic of toughness combined with hardness is fully developed by proper heat treatment. Many methods of attaching the point or wearing tip to the base have been proposed. Some of them are good, but many are entirely impracticable because they do not take into account thenecessity for providing substantially uniform metal sections to insure sound castings and proper heat treatment, nor recognize the impossibility of regularly obtaining close interchangeability of parts when making rough castings of a non-machinable' steel.

My improvements are the result of extended practice in the designing of excavating apparatus and close observation of the behavior of digging teeth in all classes ofservice and under all kinds of operating conditions. They were devised with the following objects in view, to wit :to simplify the lock between point and base while maintaining substantial uniformity as regards metal sections; to insure a tight fit by eliminating conditions making for premature contact; to eliminate excess or unnecessary metal in the point; to reinforce the nose of the base so that it will resist'side thrust of the point with a minimum resultant of spreading or breakage; and to provide a wedge bolt of such form-that it not only has greater shear .resistance, but compensates for unavoidable mislocation of cored holes, and is fool-proof in the sense that it can be applied in the correct way only.

With such and other objects in view, the nature, characteristic features and scope of the invention will more readily be understood fromthe following description taken n connection with the accompanying drawmg, wherein- Flgure 1 is a top view partly in section of a two part reversible tooth my improvements;

Figure 2 is a side elevational view of the same; 4

Figure 3 is a perspective view partly in sect on of the point; and

Figure 4 is a. perspective view of the wedge bolt. V

In the drawing, 5 represents the base and 6 represents the detachable and reversible polnt. These elements, save in the particulzlirs hereinafternoted, are or may be as usua According to my invention, the slotted or bifurcated nose portion of the base is reinconverge at the front, as at 9; are continned rearwardly preferably beyond the divislon 1O of'the base, and ultimately vanish in the body of the base. On bases of small sue the lower ribs may be omitted, when there would otherwise be interference with the operation of a wrench on the nut. The merit of the ribbed construction is that it provldes increased resistance to side thrust under dlgglng) strains, prevents spreading and eventual reakage of the nose, and acts as a guard to protect the nut from abrasive wear in SBI'VIGQ.

- The jaws of the point are joined by a web 11 that fits the slot 12 of the base. Departmg from the usual practice. the web, while of nearly the full depth of the jaws, is cut away as at 13, so as to eliminate unnecessary metal and so as to provide a fiat bearing surface 14 for a purpose hereinafter referred to, the cut out portion being of general diamond shape.

The general design, with-respect to the fit of the point and base, is such that initially there is clearance at the'tip of the nose, as indicated at 18. This is an important feature because without such clearance there would be the usual premature contact which prevents or seriously. interferes with proper seating of the point, The clearance enables embodying v Ill the taper bolt or tightening device properly to seat the poll and to tighten it :lroxn time to time is necessary in service, It not infrequently hoppens in teeth oil earlier designs that cored holes for the bolt are out ol alineiment and when the ordinary wedge bolt is applied to a condition oi this kind it shifts the point until the holes register, which puts side shear on the bolt and results in uneven pressure between the top and bottom fit of point and base, More over, the old style bolt can be and in service frequently is used in reverse position; which naturally prevents proper Wed ing action and causes looseness of the point in a short time. This brings us to another important feature of the invention, namely the means trlor initially and continuously properly seating the point and for keeping it tight in service. In providing: this feature and While utilising the principle oi the wedge, l materially depart from the usual wedge bolt which has two rounded edges and hence is capable of reversal and destructive influences as already pointed out. The Wedge bolt 15 of my invention has a flat edge 16 on the side parallel to the axis of the threaded end. l-ts tapered side 1? is rounded, The cored openings 19, 20 in the nose correspond to the cross-section of the bolt. The wedge bolt 15 is therefore foolroof in the sense that it can be applied ut one Way-the correct Way. Moreover it isimmaterinl Whether or not the cored holes are in register because the flat edge of "the bolt bearn c; on the flat surface oi the opening in the Web allows for shill and compensates for unavoidable misloca tion ol bolt openings "while at the same time providing greater shear resistance. Referring to Figs. 1 and El. will apparent that the flat edge of the bolt tallies a dash hearing at all times against the central llat bearing surface 14 in the cut away portion of the Web. Evidently then, in any construction the point must talze the correct central position on the base, and it follows that the bolt can be entered and driven home regardless of the location of the cored holes in the base.

What is claimed is:

1. A clipper tooth embodying a base bi'iurcated for the reception of a point, a point capable of reversal thereon and means For tightening the point, the point and base having relative eearanoe at the extreme nose portion out tl base for the purpose and with the result insuring}: correct seating ol the point in response to ggzhtening ellorto 2. A dipper tooth embodying a base bi'lurcatsd for the recep ion of a point, a point capable oi reversal thereon and nonre'versible means for tightening: the point the point and haying relative cl arance at the extreme nose portion the base for the purpose with the result oil insuring correst seating of the point in response to tightening ellorh i 3. A dipper tooth embodying a base and a detachable point with openings for the reception of a wedge bolt for relatively securing them, and a non-reversible wedge bolt.

4-. A dipper tooth embodying a base and a detachable point whereozl both are constructed with hearing suritaces for a tighten ing element, and a tightening element 00- operating with said bearing surfaces and shaped so as to be non-reversible and oiled tire properly to seat the point 5, A dipper tooth embodying a base and a detachable point said elements having open W ings for a tightening device, and a tightening device ell'ective to seat correctly the point regardless of casual niisalinement oi the opening,

6. A dipper tooth embodying a base and a 35 detachable point, and a wedge bolt :tor rel: atively securing thein the Wedge bolt having a flat edge bearing surface parallel to the axis of the threaded end and a rounded taper bearingsurlace. the o cnings in thefl base being correspondingly ormed, Where-- by the. bolt is a plicable one Way only.

7. A base having a bifurcated nose whereof each half is of channel cross-section.

8. A base of the bifurcated nose type, each nose element being of channel cross-section, said section stopping short of the tip of the nose and vanishing in the body of the base beyond the division thereo'll 9. A base having a bilurcated nose Wherewill of each half is provided on its outer side wall with marginal ribs to enable the nose effectively to resist side thrust incidental to digging.

10. A base having a bifurcated nose W5 whereof each half is provided with laterally directed edge reinforcements to stiffen the nose against side thrust, said reinforcements conrerging at the front and continued rearwardly beyond the division of the base.

11. A dipper tooth embodying a base having a bifurcated nose, a detachable point having" a web which enters said nose and which initially clears the frontal extremity of the nose, a point tightening element of 1m the non-reversible Wedge type, and bearings in the point and base and co-operating with the tightening element to lalte up the clearance and compel correct central positioning of the point. will 12. A point having Web connected jaws, the Web having a slot of general diamond shape and whereof the extreme rear Willi delines it flat bearing surface a tightening element. ml

13. A wedge bolt for clipper teeth, having llll a flat edge bearing surface parallel to the axis of the threaded end and a rounded taper bearing surface W 14. A point having a central web formed with a longitudinal slet theextreme rear wall of whleh defines a iia-t bearing surface for use in centering the point.

15. A point having a central web. formed 5 with a longitudinal slet,-the' extreme rear wall of which is limited vertically and defines afiat bearing surface fer use in centering the point 16. A dipper tooth, embodying a base and a reversible point constructed and arranged,

fer relative fit Without premature contact, a wedge bolt eo-operating with the point and base for application 'one way only, whereby it correctly seats the point with a minimum of shearing strain, aml means formed integral with the base to augment its resistance to side thrust and efiective"t0' shroud the ends of the belt.

In testimony whereof 1i afix my signature.

CHARLES B. ANEREWS. 

